x1, x2, y1, y2 = map(float, input().split())
ans = ((x1 - y1)**2 + (x2 - y2)**2)**0.5
print("{:.5f}".format(ans)) x1, x2, y1, y2 = map(float, input().split()) x1 map(float, input().split()) map float input().split() ().split () input split x2 y1 y2 ans = ((x1 - y1)**2 + (x2 - y2)**2)**0.5 ans ((x1 - y1)**2 + (x2 - y2)**2)**0.5 (x1 - y1)**2 + (x2 - y2)**2 (x1 - y1)**2 x1 - y1 x1 y1 2 (x2 - y2)**2 x2 - y2 x2 y2 2 0.5 print("{:.5f}".format(ans)) print "{:.5f}".format(ans) "{:.5f}".format "{:.5f}" format ans y1, y2 = map(float, input().split()) map(float, input().split()) y1 x2, y1, y2 = map(float, input().split()) map(float, input().split()) x2 y2 = map(float, input().split()) map(float, input().split()) y2 ans = ((x1 - y1)**2 + (x2 - y2)**2)**0.5 ((x1 - y1)**2 + (x2 - y2)**2)**0.5 ans x1, x2, y1, y2 = map(float, input().split()) map(float, input().split()) x1
x1, x2, y1, y2 = map(float, input().split())
ans = ((x1 - y1)**2 + (x2 - y2)**2)**0.5
print("{:.5f}".format(ans))